This invention relates to a machine suitable, for example, for forming polyester cushions.
A schematic view of a prior art machine 10 used in manufacturing molded fiber parts is shown in FIG. 1. The machine 10 includes a vacuum system 12 and fiber feed system 14 that provides fiber material to a mold system 15. In one example process, the fiber feed system 14 blows fiber to a hood 16 of the vacuum system 12. The hood 16 is arranged above the mold system 15. The prior art hood 16 uses multiple flaps 18 to regulate the amount of fiber material deposited within the mold below to vary the volume and density throughout the molded fiber part. The flaps 18 are selectively opened and closed over different portions of the mold to deposit fiber material in columns in varying amounts beneath each flap 18. Each column may have more or less fiber material than another column. The density in each column is based upon the amount in the column, for example, in articles being formed that will have a uniform thickness.
A back pressure indicative of fiber distribution within the mold is monitored by a pressure gauge as the flaps 18 are moved between open and closed positions. Actuation of the flaps 18 is sequential and relatively slow thereby increasing the cycle time. Furthermore, use of the flaps 18 does not result in a very gradual distribution of fibers across the columns within the mold.
More accuracy and flexibility in varying the distribution of fibers within the mold is desired. Moreover, it is desirable to improve the cycle times of the molding process.